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Communication measures to bridge ten millennia. [Contains glossary] (open access)

Communication measures to bridge ten millennia. [Contains glossary]

The Department of Energy created the Human Interference Task Force (HITF) in 1980 to investigate the problems connected with the postclosure, final marking of a filled nuclear waste repository. The task of the HITF is to devise a method of warning future generations not to mine or drill at that site unless they are aware of the consequences of their actions. Since the likelihood of human interference should be minimized for 10,000 years, an effective and long-lasting warning system must be designed. This report is a semiotic analysis of the problem, examining it in terms of the science or theory of messages and symbols. Because of the long period of time involved, the report recommends that a relay system of recoding messages be initiated; that the messages contain a mixture of iconic, indexical, and symbolic elements; and that a high degree of redundancy of messages be employed.
Date: April 1, 1984
Creator: Sebeok, T.A.
Object Type: Report
System: The UNT Digital Library
Risk communication in environmental restoration programs (open access)

Risk communication in environmental restoration programs

The author advocates adoption of a convergence model in place of the traditional source-receiver model of communication for communicating with members of the public who have a stake in remediation of a nearby site. The source-receiver model conceives of communication as the transmission of a message from a risk management agency (sender) to a target audience of the public (receivers). The underlying theme is that the sender intends to change the perception of the receiver of either the issue or the sender of information. The theme may be appropriate for health campaigns which seek to change public behavior; however, the author draws on her experience at a DOE site undergoing remediation to illustrate why the convergence model is more appropriate in the context of cleanup. This alternative model focuses on the Latin derivation of communication as sharing or making common to many, i.e., as involving a relationship between participants who engage in a process of communication. The focus appears to be consistent with recently issued DOE policy that calls for involving the public in identifying issues and problems and in formulating and evaluating decision alternatives in cleanup. By emphasizing context, process and participants, as opposed to senders and receivers, the …
Date: April 1, 1993
Creator: Bradbury, J.A.
Object Type: Article
System: The UNT Digital Library
Risk communication in environmental restoration programs (open access)

Risk communication in environmental restoration programs

The author advocates adoption of a convergence model in place of the traditional source-receiver model of communication for communicating with members of the public who have a stake in remediation of a nearby site. The source-receiver model conceives of communication as the transmission of a message from a risk management agency (sender) to a target audience of the public (receivers). The underlying theme is that the sender intends to change the perception of the receiver of either the issue or the sender of information. The theme may be appropriate for health campaigns which seek to change public behavior; however, the author draws on her experience at a DOE site undergoing remediation to illustrate why the convergence model is more appropriate in the context of cleanup. This alternative model focuses on the Latin derivation of communication as sharing or making common to many, i.e., as involving a relationship between participants who engage in a process of communication. The focus appears to be consistent with recently issued DOE policy that calls for involving the public in identifying issues and problems and in formulating and evaluating decision alternatives in cleanup. By emphasizing context, process and participants, as opposed to senders and receivers, the …
Date: April 1, 1993
Creator: Bradbury, J. A.
Object Type: Article
System: The UNT Digital Library
Sequestering in String Theory (open access)

Sequestering in String Theory

We study sequestering, a prerequisite for flavor-blind supersymmetry breaking in several high-scale mediation mechanisms, in compactifications of type IIB string theory. We find that although sequestering is typically absent in unwarped backgrounds, strongly warped compactifications do readily sequester. The AdS/CFT dual description in terms of conformal sequestering plays an important role in our analysis, and we establish how sequestering works both on the gravity side and on the gauge theory side. We pay special attention to subtle compactification effects that can disrupt sequestering. Our result is a step toward realizing an appealing pattern of soft terms in a KKLT compactification.
Date: April 4, 2007
Creator: Kachru, Shamit; McAllister, Liam & Sundrum, Raman
Object Type: Article
System: The UNT Digital Library
Communication across 300 generations: deterring human interference with waste deposit sites (open access)

Communication across 300 generations: deterring human interference with waste deposit sites

The conditions attendant on the deep land burial of nuclear waste products raise a number of possible scenarios to cover the necessary 10,000 years of burial. However, no matter what kind of futuristic scenario obtains, it is desirable to develop an information system indicating the locale and nature of the deposit site and the types of materials stored, along with forewarnings not to interefere with the sites. A variety of such informational sites are suggested. Attention then turns to the recipients of such messages, recognizing from the outset that the psychological/perceptual makeup of individuals across the next 300 or so generations is virtually impossible to predict, particularly since new technologies may well alter that makeup in the furture. Nevertheless, current evidence suggests that certain human characteristics may be considered universal, and that these suggest the incorporation of selected sign signification into the message system. There are other such characteristics that, while probably not intrinsic, can probably be acquired with a minimum of formal training. That still leaves much of the message content to be deliberately created and, hence, learned. The common trefoil or other developed biohazardous signs emerge as the best candidates for a generic base symbol for the buried …
Date: April 1, 1984
Creator: Tannenbaum, P.H.
Object Type: Report
System: The UNT Digital Library
Theory and measurement of the electron cloud effect. (open access)

Theory and measurement of the electron cloud effect.

Photoelectrons produced through the interaction of synchrotrons radiation and the vacuum chamber walls can be accelerated by a charged particle beam, acquiring sufficient energy to produce secondary electrons (SES) in collisions with the walls. If the secondary-electron yield (SEY) coefficient of the wall material is greater than one, a run-away condition can develop. In addition to the SEY, the degree of amplification depends on the beam intensity and temporal distribution. As the electron cloud builds up along a train of stored bunches, a transverse perturbation of the head bunch can be communicated to trailing bunches in a wakefield-like interaction with the cloud. The electron cloud effect is especially of concern for the high-intensity PEP-II (SLAC) and KEK B-factories and at the Large Hadron Collider (LHC) at CERN. An initiative was undertaken at the Advanced Photon Source (APS) storage ring to characterize the electron cloud in order to provide realistic limits on critical input parameters in the models and improve their predictive capabilities. An intensive research program was undertaken at CERN to address key issues relating to the LHC. After giving an overview, the recent theoretical and experimental results from the APS and the other laboratories will be discussed.
Date: April 29, 1999
Creator: Harkey, K. C.
Object Type: Article
System: The UNT Digital Library
Combination of Evidence in Dempster-Shafer Theory (open access)

Combination of Evidence in Dempster-Shafer Theory

Dempster-Shafer theory offers an alternative to traditional probabilistic theory for the mathematical representation of uncertainty. The significant innovation of this framework is that it allows for the allocation of a probability mass to sets or intervals. Dempster-Shafer theory does not require an assumption regarding the probability of the individual constituents of the set or interval. This is a potentially valuable tool for the evaluation of risk and reliability in engineering applications when it is not possible to obtain a precise measurement from experiments, or when knowledge is obtained from expert elicitation. An important aspect of this theory is the combination of evidence obtained from multiple sources and the modeling of conflict between them. This report surveys a number of possible combination rules for Dempster-Shafer structures and provides examples of the implementation of these rules for discrete and interval-valued data.
Date: April 1, 2002
Creator: SENTZ, KARI & FERSON, SCOTT
Object Type: Report
System: The UNT Digital Library
Phenomenological Theory of the Photoevaporation Front Instability (open access)

Phenomenological Theory of the Photoevaporation Front Instability

The dynamics of photoevaporated molecular clouds is determined by the ablative pressure acting on the ionization front. An important step in the understanding of the ensuing motion is to develop the linear stability theory for the initially flat front. Despite the simplifications introduced by the linearization, the problem remains quite complex and still draws a lot of attention. The complexity is related to the large number of effects that have to be included in the analysis: acceleration of the front, possible temporal variation of the intensity of the ionizing radiation, the tilt of the radiation flux with respect to the normal to the surface, and partial absorption of the incident radiation in the ablated material. In this paper, we describe a model where all these effects can be taken into account simultaneously, and a relatively simple and universal dispersion relation can be obtained. The proposed phenomenological model may prove to be a helpful tool in assessing the feasibility of the laboratory experiments directed towards scaled modeling of astrophysical phenomena.
Date: April 10, 2006
Creator: Ryutov, D. D.; Kane, J. O.; Mizuta, A.; Pound, M. W. & Remington, B. A.
Object Type: Article
System: The UNT Digital Library
Plasma confinement theory and transport simulation (open access)

Plasma confinement theory and transport simulation

The objectives are: (1) to advance the transport studies of tokamaks, including development and maintenance of the Magnetic Fusion Energy Database, and (2) to provide theoretical interpretation, modeling and equilibrium and stability studies for TEXT-Upgrade. Recent reports, publications, and conference presentations of the Fusion Research Center are listed.
Date: April 1, 1992
Creator: Ross, D.W.
Object Type: Report
System: The UNT Digital Library
Prospects for Advanced RF Theory and Modeling (open access)

Prospects for Advanced RF Theory and Modeling

This paper represents an attempt to express in print the contents of a rather philosophical review talk. The charge for the talk was not to summarize the present status of the field and what we can do, but to assess what we will need to do in the future and where the gaps are in fulfilling these needs. The objective was to be complete, covering all aspects of theory and modeling in all frequency regimes, although in the end the talk mainly focussed on the ion cyclotron range of frequencies (ICRF). In choosing which areas to develop, it is important to keep in mind who the customers for RF modeling are likely to be and what sorts of tasks they will need for RF to do. This occupies the first part of the paper. Then we examine each of the elements of a complete RF theory and try to identify the kinds of advances needed.
Date: April 12, 1999
Creator: Batchelor, D.B.
Object Type: Article
System: The UNT Digital Library
Assessment of the theory and hypotheses of the acidification of watersheds (open access)

Assessment of the theory and hypotheses of the acidification of watersheds

This report documents and critically assesses the evolution and status of the scientific understanding of the effects of acidic deposition on surface waters. The main conclusion is that the dominant theory of surface-water acidification fails to adequately incorporate many important factors and processes that influence surface water acidity. Some of these factors and processes are not well researched or recognized as being important by most scientists in the aquatic effects research area. 258 refs., 14 figs., 23 tabs.
Date: April 1, 1989
Creator: Krug, E.C.
Object Type: Report
System: The UNT Digital Library
A Proposed Experimental Test of the Neutrino Theory (open access)

A Proposed Experimental Test of the Neutrino Theory

The experiment outlined in this proposal has the possibility of giving an answer to the important question, 'Does the neutrino exist'? It is unfortunate that at the present time, there is no convincing experimental that neutrinos exist. Two recent articles review the status of various experiments which could give information about neutrinos. In general, these experiments give results in agreement with the predictions of beta decay theory. But actually, if even the most complete of the 'recoil type' experiments could be performed satisfactorily, all that could be concluded would be the following: the energy and momentum relationships in beta decay are consistent with the theory that the known energy deficit is carried away by a single particle. But to emphasize the fact that this would not constitute a proof of the real existence of that particle, the following quotations from the review articles should be noted. Crane says, 'All of the evidence about the neutrino is, as already pointed out, indirect in character since neutrinos have not yet been caught after leaving the nucleus. It can, of course, be argued on very general grounds that, if energy is not conserved between nucleus and electron, momentum should not be expected to …
Date: April 18, 1949
Creator: Alvarez, Luis W.
Object Type: Report
System: The UNT Digital Library
Continuum Regularization of Quantum Field Theory (open access)

Continuum Regularization of Quantum Field Theory

Possible nonperturbative continuum regularization schemes for quantum field theory are discussed which are based upon the Langevin equation of Parisi and Wu. Breit, Gupta and Zaks made the first proposal for new gauge invariant nonperturbative regularization. The scheme is based on smearing in the ''fifth-time'' of the Langevin equation. An analysis of their stochastic regularization scheme for the case of scalar electrodynamics with the standard covariant gauge fixing is given. Their scheme is shown to preserve the masslessness of the photon and the tensor structure of the photon vacuum polarization at the one-loop level. Although stochastic regularization is viable in one-loop electrodynamics, two difficulties arise which, in general, ruins the scheme. One problem is that the superficial quadratic divergences force a bottomless action for the noise. Another difficulty is that stochastic regularization by fifth-time smearing is incompatible with Zwanziger's gauge fixing, which is the only known nonperturbaive covariant gauge fixing for nonabelian gauge theories. Finally, a successful covariant derivative scheme is discussed which avoids the difficulties encountered with the earlier stochastic regularization by fifth-time smearing. For QCD the regularized formulation is manifestly Lorentz invariant, gauge invariant, ghost free and finite to all orders. A vanishing gluon mass is explicitly verified …
Date: April 1, 1986
Creator: Bern, Z.
Object Type: Report
System: The UNT Digital Library
Topics in the theory of heavy-quark systems (open access)

Topics in the theory of heavy-quark systems

Due to the kinematic and dynamic simplifications possible because of the large mass of heavy quark bound states, certain properties of these systems can be quantitatively analyzed within the framework of quantum chromodynamics. It is clear that dimensionally the size of the bound state is proportional to the inverse quark mass, and for very heavy quarkonia the radius of the system should become smaller than that of normal hadrons. When this small system interacts with external long wavelength field quanta, the natural expansion that results is of a multipole type, analogous to the familiar multipole expansion in electrodynamics. This multipole expansion has better convergence properties than the standard perturbative treatment in certain kinematic regimes, which opens up a new area for strong interaction physics calculations. More specifically, it is ideally suited to investigate soft non-perturbative effects in QCD which appear to be so crucial to present day phenomenology and the conjectured confinement mechanism.
Date: April 1, 1981
Creator: Flory, C.A.
Object Type: Report
System: The UNT Digital Library
Topics in low-dimensional field theory (open access)

Topics in low-dimensional field theory

Conformal field theory is a natural tool for understanding two- dimensional critical systems. This work presents results in the lagrangian approach to conformal field theory. The first sections are chiefly about a particular class of field theories called coset constructions and the last part is an exposition of the connection between two-dimensional conformal theory and a three-dimensional gauge theory whose lagrangian is the Chern-Simons density.
Date: April 30, 1991
Creator: Crescimanno, M.J.
Object Type: Report
System: The UNT Digital Library
Geometric perturbation theory and plasma physics (open access)

Geometric perturbation theory and plasma physics

Modern differential geometric techniques are used to unify the physical asymptotics underlying mechanics, wave theory and statistical mechanics. The approach gives new insights into the structure of physical theories and is suited to the needs of modern large-scale computer simulation and symbol manipulation systems. A coordinate-free formulation of non-singular perturbation theory is given, from which a new Hamiltonian perturbation structure is derived and related to the unperturbed structure. The theory of perturbations in the presence of symmetry is developed, and the method of averaging is related to reduction by a circle group action. The pseudo-forces and magnetic Poisson bracket terms due to reduction are given a natural asymptotic interpretation. Similar terms due to changing reference frames are related to the method of variation of parameters, which is also given a Hamiltonian formulation. These methods are used to answer a question about nearly periodic systems. The answer leads to a new secular perturbation theory that contains no ad hoc elements. Eikonal wave theory is given a Hamiltonian formulation that generalizes Whitham's Lagrangian approach. The evolution of wave action density on ray phase space is given a Hamiltonian structure using a Lie-Poisson bracket. The relationship between dissipative and Hamiltonian systems is discussed. …
Date: April 4, 1985
Creator: Omohundro, S.M.
Object Type: Report
System: The UNT Digital Library
A realistic model for quantum theory with a locality property (open access)

A realistic model for quantum theory with a locality property

A model reproducing the predictions of relativistic quantum theory to any desired degree of accuracy is described in this paper. It involves quantities that are independent of the observer's knowledge, and therefore can be called real, and which are defined at each point in space, and therefore can be called local in a rudimentary sense. It involves faster-than-light, but not instantaneous, action at distance.
Date: April 1, 1987
Creator: Eberhard, P.H.
Object Type: Report
System: The UNT Digital Library
Theory of the negative magnetoresistance in magnetic metallic multilayers (open access)

Theory of the negative magnetoresistance in magnetic metallic multilayers

The Boltzman equation is solved for a system consisting of alternating ferromagnetic normal metallic layers. The in-plane conductance of the film is calculated for two configurations: successive ferromagnetic layers aligned parallel and antiparallel to each other. Results explain the giant negative magnetoresistance encountered in these systems when an initial antiparallel arrangement is changed into a parallel configuration by application of an extemal magnetic field. The calculation depends on geometric parameters (the thicknesses of the layers); intrinsic metal parameters (number of conduction electrons, magnetization and effective masses in the layers); bulk sample properties (conductivity relaxation times); and interface scattering properties (diffuse scattering versus potential scattering at the interfaces). It is found that a large negative magnetoresistance requires, in general, considerable asymmetry in the interface scattering for the two spin orienmtions. All qualitative features of the experiments are reproduced. Quantitative agreement can be achieved with sensible values of the parameters. The effect can be conceptually explained based on considerations of phase-space availability for an electron of a given spin orientation as it travels through the multilayer sample in the various configurations and traverses the interfaces.
Date: April 1, 1993
Creator: Hood, R. Q. & Falicov, L. M.
Object Type: Article
System: The UNT Digital Library
1994 International Sherwood Fusion Theory Conference (open access)

1994 International Sherwood Fusion Theory Conference

This report contains the abstracts of the paper presented at the 1994 International Sherwood Fusion Theory Conference.
Date: April 1, 1994
Creator: unknown
Object Type: Article
System: The UNT Digital Library
X-ray laser related experiments and theory at Princeton (open access)

X-ray laser related experiments and theory at Princeton

This paper describes a new system for the development of an x-ray laser in the wavelength region from 5 nm to 1 nm utilizing a Powerful Sub-Picosecond Laser (PP-Laser) of expected peak power up to 0.5 TW in a 300 fs pulse. Soft x-ray spectra generated by the interaction of the PP-Laser beam with different targets are presented and compared to the spectra generated by a much less intense laser beam (20--30 GW). A theoretical model for the interaction of atoms with such a strong laser EM field is also briefly discussed. The development of additional amplifiers for the recombining soft x-ray laser and the design of a cavity are presented from the point of view of applications for x-ray microscopy and microlithography. This overview concludes with the presentation of recent results on the quenching of spontaneous emission radiation and its possible effect on the absolute intensity calibration of soft x-ray spectrometers. 26 refs., 18 figs.
Date: April 1, 1989
Creator: Suckewer, S.
Object Type: Article
System: The UNT Digital Library
How Religion Frames Health Norms: A Structural Theory Approach (open access)

How Religion Frames Health Norms: A Structural Theory Approach

This review looks at the religious communities influence health-related behaviors of adherents in important ways for public health promotion. Questions remain about the processes involved and resultant health promotion actions of the religious adherents.
Date: April 9, 2018
Creator: Mpofu, Elias
Object Type: Article
System: The UNT Digital Library
Theory-Based Failure Modes and Effect Analysis for Medication Errors (open access)

Theory-Based Failure Modes and Effect Analysis for Medication Errors

This article presents a hybrid decision-making approach to assigning different weights to risk factors and considering the uncertainty in the ranking process in the Failure Modes and Effect Analysis (FMEA) technique. Findings highlight improper medication administration as the main failure mode, which can result in a fatality or patient injury and the utilization of multiple-criteria decision-making methods in combination with Z-number as a useful tool in the healthcare management field.
Date: April 1, 2021
Creator: Ghoushchi, Saeid Jafarzadeh; Dorosti, Shadi; Ab Rahman, Mohd Nizam; Khakifirooz, Marzieh & Fathi, Mahdi
Object Type: Article
System: The UNT Digital Library
Theory and modelling of quench in cable-in-conduit superconducting magnets (open access)

Theory and modelling of quench in cable-in-conduit superconducting magnets

A new simple, self consistent theoretical model is presented that describes the phenomena of quench propagation in Cable-In-Conduit superconducting magnets. The model (Quencher) circumvents many of the difficulties associated with obtaining numerical solutions in more general existing models. Specifically, a factor of 30-50 is gained in CPU time over the general, explicit time dependent codes used to study typical quench events. The corresponding numerical implementation of the new model is described and the numerical results are shown to agree very well with those of the more general models, as well as with experimental data. Further, well justified approximations lead to the MacQuench model that is shown to be very accurate and considerably more efficient than the Quencher model. The MacQuench code is suitable for performing quench studies on a personal computer, requiring only several minutes of CPU time. In order to perform parametric studies on new conductor designs it is required to utilize a model such as MacQuench because of the high computational efficiency of this model. Finally, a set of analytic solutions for the problem of quench propagation in Cable-In-Conduit Conductors is presented. These analytic solutions represent the first such results that remain valid for the long time scales …
Date: April 1, 1994
Creator: Shajii, A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Application of the classical theory of electrons in gases to multiwire proportional and drift chambers (open access)

Application of the classical theory of electrons in gases to multiwire proportional and drift chambers

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Date: April 1, 1974
Creator: Palladino, V. & Sadoulet, B.
Object Type: Report
System: The UNT Digital Library